Climate Variability and Plant Physiological Responses across Diverse Ecological Zones

Abstract

Climate variability, expressed through fluctuating temperature, precipitation and atmospheric carbon dioxide, exerts strong control over plant physiological processes and ecosystem function. This article reviews how photosynthesis, water relations, stomatal behaviour and phenology respond to climatic variation across tropical, arid, temperate, alpine and boreal zones. Evidence indicates that tropical species often operate near their thermal limits with restricted acclimation capacity, dryland plants rely on water-conserving and stress-tolerant strategies that may be exceeded by intensified droughts, and cold-zone vegetation experiences both relaxed temperature limitation and heightened risks from frost mismatch and disturbance. Elevated carbon dioxide can enhance carbon gain and water-use efficiency, but benefits are constrained by nutrients, heat and acclimation. Phenotypic plasticity and combined-stress tolerance emerge as key determinants of resilience. The synthesis highlights research priorities for crop improvement, conservation planning and multi-factor field experimentation across ecological zones.